Flexible sensor system for prognostic health monitoring of composite aerostructures

Abstract

A sensor array system includes a skin. The sensor array system includes a lattice network coupled to a portion of the skin. The lattice network includes a plurality of interconnects and a plurality of nodes. The plurality of nodes are respectively defined by an intersection of two or more interconnects of the plurality of interconnects. The sensor array system includes a first sensor electrically connected to the lattice network at a first node of the plurality of nodes.

What is claimed is: 
     
       1. A gas turbine engine comprising:
 an engine core having a longitudinal center axis; 
 a non-rotating, inner structure disposed circumferentially about the engine core; and 
 an acoustic panel coupled to a surface of the inner structure, the acoustic panel including a back skin adjacent the inner structure, a face skin, and a core structure disposed between the back skin and the face skin, the acoustic panel further comprising a sensor array comprising: 
 a lattice network mounted directly onto a portion of the back skin, the lattice network including a plurality of interconnects and at least one node defined by an intersection of two or more interconnects of the plurality of interconnects; and
 a first sensor electrically connected to the lattice network at a first node of the at least one node. 
 
 
     
     
       2. The gas turbine engine of  claim 1 , wherein the portion of the back skin is disposed on a side of the back skin facing the core structure. 
     
     
       3. The gas turbine engine of  claim 1 , further comprising a thermal blanket disposed between the inner structure and the acoustic panel. 
     
     
       4. The gas turbine engine of  claim 3 , wherein
 the portion of the back skin is disposed on a side of the back skin facing away from the core structure, and 
 the sensor array is disposed between the thermal blanket and the back skin. 
 
     
     
       5. The gas turbine engine of  claim 1 , wherein the first sensor is a temperature sensor. 
     
     
       6. The gas turbine engine of  claim 5 , wherein the sensor array further comprises a second sensor electrically connected to the lattice network at a second node of the at least one node, wherein the second sensor is different than the first sensor. 
     
     
       7. The gas turbine engine of  claim 6 , wherein the second sensor includes a strain sensor or a piezoelectric sensor. 
     
     
       8. A gas turbine engine comprising:
 a bypass air duct; 
 an engine core having a longitudinal center axis; 
 a non-rotating, inner fixed structure disposed circumferentially about the engine core, the inner fixed structure disposed radially inward of the bypass air duct; and 
 a composite skin directly coupled to the inner fixed structure radially inward of the bypass air duct, the composite skin further comprising a sensor array comprising:
 a lattice network mounted directly onto a portion of the composite skin, the lattice network including a plurality of interconnects forming a plurality of nodes, each node of the plurality of nodes defined by an intersection of two or more interconnects of the plurality of interconnects; and 
 a plurality of resistance temperature detectors, each resistance temperature detector of the plurality of resistance temperature detectors electrically connected to the lattice network at a respective node of the plurality of nodes. 
 
 
     
     
       9. The gas turbine engine of  claim 8 , further comprising a thermal blanket disposed between the inner fixed structure and the composite skin. 
     
     
       10. The gas turbine engine of  claim 9 , wherein the sensor array is disposed between the composite skin and the thermal blanket. 
     
     
       11. The gas turbine engine of  claim 8 , further comprising a computing system electrically connected to the sensor array, the computing system configured to detect a thermal excursion for an operational condition of the gas turbine engine with an electrical resistance value provided by the plurality of resistance temperature detectors. 
     
     
       12. The gas turbine engine of  claim 8 , wherein the sensor array further includes an input-output circuit electrically connected to the lattice network at a second node of the plurality of nodes, wherein the input-output circuit includes at least one of an input circuit and an output circuit. 
     
     
       13. The gas turbine engine of  claim 12 , wherein: the composite skin includes an aperture extending through the composite skin at a location proximal to the second node, and the input-output circuit includes at least one conductor extending through the aperture. 
     
     
       14. The gas turbine engine of  claim 8 , wherein the surface of the composite skin is a non-planar surface. 
     
     
       15. The gas turbine engine of  claim 8 , wherein: the composite skin includes a first layer and a second layer adjacent to the first layer, the first layer including the surface of the composite skin, and the lattice network is coupled to the portion of the composite skin between the first layer and the second layer.